Router problem after Windows 10 installation

I have just installed Windows 10 and have stuck a problem with my internet connection.
I have a TPLink Archer D7 double band modem/router and adapter, 2.4ghz and 5ghz. In the previous installation Windows 7, It indicated both bands were connected.
At present on booting up it connects to the 2.4ghz and the 5ghz is shown as Network 2, this has to be connected manually each time.
I assume that this can be overcome but have no idea as to how; any suggestions?

By connected do you mean supplying the key or just asking it to connect?
The router won't use both connections at once, it will prefer one and if connection via that isn't possible it will use the other.

Attached is a screen shot, I hope I am clear enough; The first attachment (see message bottom right hand corner, is the same as windows 7 and occasionally now on W10. I have labelled the two bands High and Low, "High" regularly drops out and I have to connect manually (no key)
The second screen shot is the message often received as I try to reconnect to "High"
I hope that all makes sense.